MAC Address Lookup
Look up the hardware vendor (OUI) for any MAC, normalise across formats (colon / dash / Cisco dot / bare), and classify as unicast / multicast / broadcast + universal / locally-administered. 300+ bundled OUI prefixes. Free and 100% private.
What is the MAC Address Lookup?
MAC Address Lookup parses any MAC address you paste — colon-separated, dash-separated, Cisco dot-form, bare 12-hex, with or without spaces — then resolves the leading 24-bit OUI against a curated vendor table covering 300+ of the most-deployed manufacturer prefixes (Apple, Cisco, Intel, Samsung, Google, Amazon, Microsoft, HP, Dell, Lenovo, Asus, Raspberry Pi, Espressif, Sonos, Roku, Sony, Nintendo, Netgear, TP-Link, D-Link and many more). It classifies the address as unicast / multicast / broadcast (FF:FF:…) and reports whether it's universally administered (IEEE-assigned) or locally administered (Docker, randomised privacy MAC, virtual NIC). Five canonical format variants are produced — lower-case colon, UPPER-case colon, dash, Cisco dot-quad and bare 12-hex — each with a one-click copy button. We intentionally don't ship the full IEEE OUI registry (~50 000 entries × ~5 MB) because the curated 300+ covers the prefixes home networks actually encounter. Pure functions, no network.
How to use it
- Paste a MAC in any format — colon / dash / Cisco dot / bare hex.
- See the vendor lookup, OUI prefix and classification at the top.
- Copy any of the 5 canonical format variants with one click.
- Use the preset buttons to test Apple / Cisco / Raspberry Pi / broadcast samples.
Benefits
- 300+ hand-curated OUI prefixes covering Apple, Cisco, Intel, Samsung, Google, Amazon, Microsoft, HP, Dell, Lenovo, Asus, Pi, Espressif, Sonos, Roku, Sony, Nintendo, Netgear, TP-Link and more.
- Accepts every common MAC format: AA:BB:CC:DD:EE:FF, AA-BB-CC-DD-EE-FF, AABB.CCDD.EEFF (Cisco), AABBCCDDEEFF.
- Five canonical output formats (lower colon, UPPER colon, dash, Cisco dot, bare) — each with a copy button.
- Classifies unicast / multicast / broadcast and universal / locally-administered.
- Recognises locally-administered MACs (Docker, randomised privacy, virtual NICs) and skips vendor lookup honestly.
- Preset buttons for Apple / Cisco / Pi / broadcast so you can try the tool in one click.
- 100% offline — the OUI table is bundled with the page, no API call.
- Persists your last MAC in localStorage for one-click resume.
Frequently asked questions
Why isn't my MAC's vendor showing?
Three possibilities: (1) the MAC's OUI isn't in our curated 300-entry table — we cover the high-traffic prefixes only; (2) the address is locally-administered (Docker, randomised iOS/Android privacy MAC, virtual NIC) so it has no IEEE-assigned vendor; (3) you typed an invalid MAC. The classification panel calls out (2).
Why not ship the full IEEE OUI registry?
It's ~50 000 entries and ~5 MB — a huge cost for a static page. Our curated 300+ covers Apple, Cisco, Intel, Samsung, Google, Amazon, Microsoft, HP, Dell, Lenovo, Asus, Pi, Espressif and more — which is what users actually scan in 95% of cases. We're open to PRs adding more prefixes.
What's the difference between universal and locally-administered?
Bit 2 of the first byte. When 0, the MAC was assigned by IEEE to a real manufacturer (and we look up the OUI). When 1, the MAC was set by software — common in Docker containers (02:42:...), VPN tunnels, iOS/Android privacy MAC randomisation, virtual machines and wired NICs you manually configured.
What's the multicast bit?
Bit 1 of the first byte. When set, the MAC is a multicast address — used by mDNS, IPv6 neighbor discovery, video streaming, gaming and some industrial protocols. FF:FF:FF:FF:FF:FF is the all-ones broadcast.
Why are Apple MACs sometimes randomised?
iOS and macOS use 'private MAC' (randomised, locally-administered) when joining unknown Wi-Fi networks. Those addresses won't have an Apple OUI lookup — the classification panel flags them as locally-administered.
Does this work on IPv6 EUI-64 addresses?
Partially — the EUI-64 includes a 64-bit modified MAC. Strip the middle 16 bits (FF FE) and the OUI lookup applies. For now this tool only handles 48-bit MACs.
Can I paste a list of MACs?
Not in this version — it's single-MAC focused. For lists, use the Duplicate Line Remover to clean first then paste one at a time.
What's the OUI exactly?
The first 24 bits (3 bytes) of a MAC address. IEEE assigns each manufacturer a unique OUI, then the manufacturer fills in the bottom 24 bits however they like.
Do randomised iOS MACs change every time?
Per Wi-Fi network, yes — iOS picks a fresh private MAC for each SSID it joins. The randomised MAC is still locally-administered, so our classification reports it correctly.
Is anything uploaded?
No. The OUI table is bundled with the page and the lookup is a pure browser computation.
How do I know if a MAC is real?
If the OUI lookup returns a vendor, it's almost certainly real. If the MAC is locally-administered, it was set by software — it could be real (Docker) or fake (mac-spoof testing).